A Critical Test of the Hammett Acidity Function

1972 ◽  
Vol 50 (4) ◽  
pp. 581-583 ◽  
Author(s):  
Keith Yates ◽  
Stanley A. Shapiro
Keyword(s):  
Sulfuric Acid ◽  
Aromatic Amines ◽  
Acidity Function ◽  
Experimental Uncertainty ◽  
Critical Test ◽  
Hammett Acidity Function ◽  
Primary Aromatic Amines

The applicability of the H0 acidity function to primary aromatic amines in general has been tested by using a set of five aniline indicators bearing no nitro-substituents. Up to 45% sulfuric acid the scale generated by these bases is the same (within experimental uncertainty) as that based entirely on nitro-anilines.

Acidity functions of hydrochloric acid, perchloric acid, and sulfuric acid and pKa values of some primary aromatic amines in 50% volume/volume aqueous ethanol

1977 ◽  
Vol 42 (1) ◽  
pp. 162-165 ◽  
Author(s):  
William N. White ◽  
Thomas Vogelmann ◽  
Michael Morse ◽  
Hilda S. White
Keyword(s):  
Sulfuric Acid ◽  
Hydrochloric Acid ◽  
Perchloric Acid ◽  
Aromatic Amines ◽  
Aqueous Ethanol ◽  
Pka Values ◽  
Primary Aromatic Amines ◽  
Acidity Functions

Protonation of polyacid organic bases. III. Hammett acidity function H+ for aqueous sulfuric acid

1968 ◽  
Vol 33 (6) ◽  
pp. 1687-1692 ◽  
Author(s):  
P. Vetešník ◽  
J. Bielavský ◽  
M. Večeřa
Keyword(s):  
Sulfuric Acid ◽  
Acidity Function ◽  
Organic Bases ◽  
Aqueous Sulfuric Acid ◽  
Hammett Acidity Function

Determination of migration of 25 primary aromatic amines from food contact plastic materials by gas chromatographymass spectrometry

2013 ◽  
Vol 31 (1) ◽  
pp. 46 ◽  
Author(s):  
Ying LI ◽  
Chengfa LI ◽  
Daoqing XIAO ◽  
Feng LIANG ◽  
Zhinan CHEN ◽  
...  
Keyword(s):  
Aromatic Amines ◽  
Food Contact ◽  
Plastic Materials ◽  
Primary Aromatic Amines

Preparation and Characterization of a Novel Room Temperature Dicationic Ionic Liquid and its Application in the Synthesis of Xanthenediones Under Solvent-Free Conditions

2018 ◽  
Vol 21 (8) ◽  
pp. 602-608 ◽  
Author(s):  
Zainab Ehsani-Nasab ◽  
Ali Ezabadi
Keyword(s):  
Ionic Liquid ◽  
Room Temperature ◽  
Reaction Times ◽  
Significant Loss ◽  
Solvent Free ◽  
Acidity Function ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Hammett Acidity Function ◽  
Dicationic Ionic Liquid

Aim and Objective: In the present work, 1, 1’-sulfinyldiethylammonium bis (hydrogen sulfate) as a novel room temperature dicationic ionic liquid was synthesized and used as a catalyst for xanthenediones synthesis. Material and Method: The dicationic ionic liquid has been synthesized using ethylamine and thionyl chloride as precursors. Then, by the reaction of [(EtNH2)2SO]Cl2 with H2SO4, [(EtNH2)2SO][HSO4]2 was prepared and after that, it was characterized by FT-IR, 1H NMR, 13C NMR as well as Hammett acidity function. This dicationic ionic liquid was used as a catalyst for the synthesis of xanthenediones via condensation of structurally diverse aldehydes and dimedone under solvent-free conditions. The progress of the reaction was monitored by thin layer chromatography (ethyl acetate/n-hexane = 3/7). Results: An efficient solvent-free method for the synthesis of xanthenediones has been developed in the presence of [(EtNH2)2SO][HSO4]2 as a powerful catalyst with high to excellent yields, and short reaction times. Additionally, recycling studies have demonstrated that the dicationic ionic liquid can be readily recovered and reused at least four times without significant loss of its catalytic activity. Conclusion: This new dicationic ionic liquid can act as a highly efficient catalyst for xanthenediones synthesis under solvent-free conditions.

Catalyst- and solvent-free Csp2-H functionalization of 4-hydroxycoumarins via C-3 dehydrogenative aza-coupling under ball-milling

2021 ◽  
Author(s):  
Goutam Brahmachari ◽  
Indrajit Karmakar ◽  
Pintu Karmakar
Keyword(s):  
Ball Milling ◽  
Aromatic Amines ◽  
Solvent Free ◽  
One Pot ◽  
Biologically Relevant ◽  
Tert Butyl ◽  
Three Component Reaction ◽  
Primary Aromatic Amines

A one-pot procedure for the synthesis of biologically relevant coumarin-hydrazones by a three-component reaction between 4-hydrocoumarins, primary aromatic amines and tert-butyl nitrite under ball-milling in the absence of any catalyst/additive...

scholarly journals Synthesis of Organic Ligands via Reactions of 4-Benzoyl-5-phenylamino-2,3-dihydrothiophene-2,3-dione with N-Nucleophiles

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Hassan Kabirifard ◽  
Pardis Hafez Taghva ◽  
Hossein Teimouri ◽  
Niloofar Koosheshi ◽  
Parastoo Javadpour ◽  
...  
Keyword(s):  
High Temperature ◽  
Carbonyl Group ◽  
Aromatic Amines ◽  
Room Temperature ◽  
Organic Ligands ◽  
Carboxyl Group ◽  
Primary Aromatic Amines

The reaction of 4-benzoyl-5-phenylamino-2,3-dihydrothiophene-2,3-dione (1) with aminoheteroaryls, lamotrigine, 1,3-diaminoheteroaryls, dapsone, NH2R (hydroxylamine, DL-1-phenylethylamine, and metformin), and 4,4′-bipyridine in THF/H2O (1 : 1) at room temperature led to 3-N-phenylthiocarbamoyl-2-butenamides 2–5, while that with naphthylamines and 1,3-phenylenediamine in ethanol at high temperature led to 5-phenylamino-2,5-dihydrothiophene-2-ones 6–8 as organic ligands in the medium to good yields. These showed the nucleophilic attacks of N-nucleophiles, except primary aromatic amines, on thioester carboxyl group (C-2) of thiophene-2,3-dione ring 1. However, the nucleophilic attacks of primary aromatic amines on the carbonyl group (C-3) of thiophene-2,3-dione 1 occurred in the form of substituted thiophenes.

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